Neuroprotective Compounds Research Articles

EST79232 and EST79376, Two Novel Sigma-1 Receptor Ligands, Exert Neuroprotection on Models of Motoneuron Degeneration.

Motor neuron diseases (MNDs) include sporadic and hereditary neurological disorders characterized by progressive degeneration of motor neurons (MNs). Sigma-1 receptor (Sig-1R) is a protein enriched in MNs, and mutations on its gene lead to various types of MND. Previous studies have suggested that Sig-1R is a target to prevent MN degeneration. In this study, two novel synthesized Sig-1R ligands, coded EST79232 and EST79376, from the same chemical series, with the same scaffold and similar physicochemical properties but opposite functionality on Sig-1R, were evaluated as neuroprotective compounds to prevent MN degeneration. We used an in vitro model of spinal cord organotypic cultures under chronic excitotoxicity and two in vivo models, the spinal nerve injury and the superoxide dismutase 1 (SOD1)G93A mice, to characterize the effects of these Sig-1R ligands on MN survival and modulation of glial reactivity. The antagonist EST79376 preserved MNs in vitro and after spinal nerve injury but was not able to improve MN death in SOD1G93A mice. In contrast, the agonist EST79232 significantly increased MN survival in the three models of MN degeneration evaluated and had a mild beneficial effect on motor function in SOD1G93A mice. In vivo, Sig-1R ligand EST79232 had a more potent effect on preventing MN degeneration than EST79376. These data further support the interest in Sig-1R as a therapeutic target for neurodegeneration.

Biological Potential, Gastrointestinal Digestion, Absorption, and Bioavailability of Algae-Derived Compounds with Neuroprotective Activity: A Comprehensive Review.

Currently, there is no known cure for neurodegenerative disease. However, the available therapies aim to manage some of the symptoms of the disease. Human neurodegenerative diseases are a heterogeneous group of illnesses characterized by progressive loss of neuronal cells and nervous system dysfunction related to several mechanisms such as protein aggregation, neuroinflammation, oxidative stress, and neurotransmission dysfunction. Neuroprotective compounds are essential in the prevention and management of neurodegenerative diseases. This review will focus on the neurodegeneration mechanisms and the compounds (proteins, polyunsaturated fatty acids (PUFAs), polysaccharides, carotenoids, phycobiliproteins, phenolic compounds, among others) present in seaweeds that have shown in vivo and in vitro neuroprotective activity. Additionally, it will cover the recent findings on the neuroprotective effects of bioactive compounds from macroalgae, with a focus on their biological potential and possible mechanism of action, including microbiota modulation. Furthermore, gastrointestinal digestion, absorption, and bioavailability will be discussed. Moreover, the clinical trials using seaweed-based drugs or extracts to treat neurodegenerative disorders will be presented, showing the real potential and limitations that a specific metabolite or extract may have as a new therapeutic agent considering the recent approval of a seaweed-based drug to treat Alzheimer’s disease.

Neuroprotective Effects and Therapeutic Potential of the Citrus Flavonoid Hesperetin in Neurodegenerative Diseases.

Neurodegenerative disorders affect more than fifty million Americans each year and represent serious health threats as the population ages. Neuroinflammation and oxidative stress are critical in the onset, progression, and pathogenesis of neurodegenerative diseases such as Alzheimer’s (AD), Parkinson’s (PD), and amyotrophic lateral sclerosis (ALS). A wide range of natural compounds has been investigated because of their antioxidant, anti-inflammatory, and neuroprotective properties. The citrus flavonoid hesperetin (HPT), an aglycone of hesperidin found in oranges, mandarins, and lemons, has been extensively reported to exert neuroprotective effects in experimental models of neurogenerative diseases. This review has compiled multiple studies on HPT in both in vivo and in vitro models to study neurodegeneration. We focused on the modulatory effects of hesperetin on the release of cellular anti-inflammatory and antioxidative stress mediators. Additionally, this review discusses the hesperetin effect in maintaining the levels of microRNA (miRNA) and modulating autophagy as it relates to hesperetin’s protective mechanisms against neurodegeneration. Moreover, this review is focused on providing experimental data for hesperetin’s potential as a neuroprotective compound and discusses reported evidence that HPT crosses the blood–brain barrier. In summary, this review shows the evidence available in the literature to indicate the efficacy of hesperetin in delaying the onset of neurodegenerative diseases.

11,12-Diacetyl-carnosol Protects SH-SY5Y Cells from Hydrogen Peroxide Damage through the Nrf2/HO-1 Pathway.

Background Oxidative stress-induced neurotoxicity plays a key role in Alzheimer's disease (AD). 11,12-Diacetyl-carnosol (NO.20), an acetylated derivative of carnosol extracted from rosemary, displays a high antioxidative effect in vitro. Purpose We investigated the neuroprotective effect of NO.20 on H2O2-induced neurotoxicity in human neuroblastoma SH-SY5Y cells and its possible mechanism. Results We found that NO.20 pretreatment (1 μM for 1 h) had cytoprotective effects and weakened H2O2-induced damage in SH-SY5Y cells by reducing viability loss, apoptotic rate, and reactive oxygen species production. In addition, NO.20 inhibited H2O2-induced mitochondrial dysfunctions: it alleviated mitochondrial membrane potential loss and cytochrome c release, decreased the Bax/Bcl-2 ratio, and reduced caspase-3 expression. NO.20 also downregulated malondialdehyde and upregulated glutathione. Furthermore, NO.20 pretreatment caused the nuclear translocation of the transcription factor NF-E2-related factor 2 (Nrf2), increasing heme oxygenase-1 (HO-1) expression in SH-SY5Y cells. Notably, we found that silencing Nrf2 using small interfering RNA (siRNA) suppressed the NO.20-induced HO-1 expression and abolished the neuroprotective effect of NO.20. Conclusion These results demonstrate that NO.20 protects SH-SY5Y cells from H2O2-induced neurotoxicity by activating the Nrf2/HO-1 pathway. Thus, the neuroprotective and antioxidative stress effects of NO.20 may make it a promising neuroprotective compound for AD treatment.

Screening neuroprotective compounds in herpes-induced Alzheimer's disease cell and 3D tissue models

Alzheimer's Disease (AD) is a neurodegenerative disorder that can cause life-altering and debilitating cognitive decline. AD's etiology is poorly understood, and no disease-modifying therapeutics exist. Here, we describe the use of 2D and 3D tissue culture models of herpesvirus-induced AD, which recapitulate hallmark disease features of plaque formation, gliosis, neuroinflammation, and impaired neuronal signaling, to screen a panel of 21 medications, supplements, and nutraceuticals with purported neuroprotective benefits. This screen identified green tea catechins and resveratrol as having strong anti-plaque properties, functional neuroprotective benefits, and minimal neurotoxicity, providing support for their further investigation as AD preventives and therapies. Two other candidates, citicoline and metformin, reduced plaque formation and were minimally toxic, but did not protect against virus-induced impairments in neuronal signaling. This study establishes a simple platform for rapidly screening and characterizing AD compounds of interest in 2D and 3D human cortical tissue models representing physiologically relevant disease features.

Curcumin Facilitates Aryl Hydrocarbon Receptor Activation to Ameliorate Inflammatory Astrogliosis.

Curcumin is an anti-inflammatory and neuroprotective compound in turmeric. It is a potential ligand of the aryl hydrocarbon receptor (AhR) that mediates anti-inflammatory signaling. However, the AhR-mediated anti-inflammatory effect of curcumin within the brain remains unclear. We investigated the role of AhR on the curcumin effect in inflammatory astrogliosis. Curcumin attenuated lipopolysaccharide (LPS)-induced proinflammatory IL-6 and TNF-α gene expression in primary cultured rat astrocytes. When AhR was knocked down, LPS-induced IL-6 and TNF-α were increased and curcumin-decreased activation of the inflammation mediator NF-κB p65 by LPS was abolished. Although LPS increased AhR and its target gene CYP1B1, curcumin further enhanced LPS-induced CYP1B1 and indoleamine 2,3-dioxygenase (IDO), which metabolizes tryptophan to AhR ligands kynurenine (KYN) and kynurenic acid (KYNA). Potential interactions between curcumin and human AhR analyzed by molecular modeling of ligand–receptor docking. We identified a new ligand binding site on AhR different from the classical 2,3,7,8-tetrachlorodibenzo-p-dioxin site. Curcumin docked onto the classical binding site, whereas KYN and KYNA occupied the novel one. Moreover, curcumin and KYNA collaboratively bound onto AhR during molecular docking, potentially resulting in synergistic effects influencing AhR activation. Curcumin may enhance the inflammation-induced IDO/KYN axis and allosterically regulate endogenous ligand binding to AhR, facilitating AhR activation to regulate inflammatory astrogliosis.

Neuroepigenetic Mechanisms of Action of Ultrashort Peptides in Alzheimer's Disease.

Epigenetic regulation of gene expression is necessary for maintaining higher-order cognitive functions (learning and memory). The current understanding of the role of epigenetics in the mechanism of Alzheimer’s disease (AD) is focused on DNA methylation, chromatin remodeling, histone modifications, and regulation of non-coding RNAs. The pathogenetic links of this disease are the misfolding and aggregation of tau protein and amyloid peptides, mitochondrial dysfunction, oxidative stress, impaired energy metabolism, destruction of the blood–brain barrier, and neuroinflammation, all of which lead to impaired synaptic plasticity and memory loss. Ultrashort peptides are promising neuroprotective compounds with a broad spectrum of activity and without reported side effects. The main aim of this review is to analyze the possible epigenetic mechanisms of the neuroprotective action of ultrashort peptides in AD. The review highlights the role of short peptides in the AD pathophysiology. We formulate the hypothesis that peptide regulation of gene expression can be mediated by the interaction of short peptides with histone proteins, cis- and transregulatory DNA elements and effector molecules (DNA/RNA-binding proteins and non-coding RNA). The development of therapeutic agents based on ultrashort peptides may offer a promising addition to the multifunctional treatment of AD.

Solubility improvement of gallic acid in water through cocrystal formation with the solvent-drop grinding method and tartaric acid as co-former

Background: Quality, safety, and efficacy are required in pharmaceutical preparations on the market. The role of tested active substances and additives in producing a product formula that is stable, consistent, and meets standards. Solubility is an important parameter for achieving systemic drug concentration and pharmacological response. Cocrystals, for example, have been studied extensively to increase their solubility. Solvent-drop grinding is used to combine active pharmaceutical substances with co-formers into a single crystal unit. Gallic acid is an antioxidant, antimicrobial, anti-inflammatory, anticancer, cardioprotective, gastroprotective, and neuroprotective chemical compound. It is soluble in water thus used to make cocrystals. Also, tartaric acid is crystallised, inert, and easily soluble in water, so it is a natural choice as a co-former. Objectives: Solvent-drop grinding was used to characterise the gallic acid cocrystal formation with tartaric acid co-former, and the effect of gallic acid cocrystal formation with tartaric acid as a co-former was tested using Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Method: The ratios of gallic acid cocrystals to tartaric acid co-formers were 1:0, 1:1, and 2:1. After crushing gallic and tartaric acids for four minutes, a few drops of ethanol solvent were added until the mixture was homogeneous. Result: There was an increase in the cocrystal solubility test. The presence of hydrogen bonds between the co-formers of gallic and tartaric acids is indicated by a wavenumber shift in the cocrystal's infrared spectrum. Furthermore, each cocrystal creates a new peak in the X-ray pattern, indicating that hydrogen bonds formed cocrystals. Conclusion: The co-crystallisation method can increase the solubility of gallic acid in water by 1.21 times.

Discovery of Azaindolin-2-One as a Dual Inhibitor of GSK3β and Tau Aggregation with Potential Neuroprotective Activity.

The inhibition of glycogen synthase kinase 3β (GSK3β) activity through pharmacological intervention represents a promising approach for treating challenging neurodegenerative disorders like Alzheimer’s disease. Similarly, abnormal tau aggregate accumulation in neurons is a hallmark of various neurodegenerative diseases. We introduced new dual GSK3β/tau aggregation inhibitors due to the excellent clinical outcome of multitarget drugs. Compound (E)-2f stands out among the synthesized inhibitors as a promising GSK3β inhibitor (IC50 1.7 µM) with a pronounced tau anti-aggregation effect in a cell-based model of tauopathy. Concurrently, (E)-2f was demonstrated to be non-toxic to normal cells, making it a promising neuroprotective lead compound that needs further investigation.

Retinal pathology in spontaneous opticospinal experimental autoimmune encephalitis mice

Retinal ganglion cells (RGC) are lost as a sequela of optic nerve inflammation in myelin oligodendrocyte glycoprotein antibody associated disease (MOGAD), but the mechanisms of injury remain incompletely understood and there remains a need to characterize the murine model of MOGAD. Several studies have shown that RGC loss occurs in association with optic neuritis in MOG35–55 experimental autoimmune encephalomyelitis (EAE), but retinal pathology has not been studied in the double transgenic opticospinal EAE (OSE) model, in which animals develop spontaneous disease associated with MOG35–55 peptide specific T cells and B cells producing MOG-specific antibodies. Herein, we show that at 8-weeks OSE mice develop optic nerve inflammation, reactive astrogliosis, and RGC loss. By 10-weeks of age, affected mice have a 50% reduction in RGCs as compared to age matched wild type mice without EAE. The retinal pathology that ensues from spontaneous optic neuritis in OSE mice mirrors that seen following human optic neuritis and may be a useful model for screening neuroprotective compounds for MOGAD and other diseases with optic neuritis.

In Vivo Dopamine Neuron Imaging-Based Small Molecule Screen Identifies Novel Neuroprotective Compounds and Targets.

Parkinson’s disease (PD) is the second most common neurodegenerative disorder with prominent dopamine (DA) neuron degeneration. PD affects millions of people worldwide, but currently available therapies are limited to temporary relief of symptoms. As an effort to discover disease-modifying therapeutics, we have conducted a screen of 1,403 bioactive small molecule compounds using an in vivo whole organism screening assay in transgenic larval zebrafish. The transgenic model expresses the bacterial enzyme nitroreductase (NTR) driven by the tyrosine hydroxylase (th) promotor. NTR converts the commonly used antibiotic pro-drug metronidazole (MTZ) to the toxic nitroso radical form to induce DA neuronal loss. 57 compounds were identified with a brain health score (BHS) that was significantly improved compared to the MTZ treatment alone after FDR adjustment (padj<0.05). Independently, we curated the high throughput screening (HTS) data by annotating each compound with pharmaceutical classification, known mechanism of action, indication, IC50, and target. Using the Reactome database, we performed pathway analysis, which uncovered previously unknown pathways in addition to validating previously known pathways associated with PD. Non-topology-based pathway analysis of the screening data further identified apoptosis, estrogen hormone, dipeptidyl-peptidase 4, and opioid receptor Mu1 to be potentially significant pathways and targets involved in neuroprotection. A total of 12 compounds were examined with a secondary assay that imaged DA neurons before and after compound treatment. The z’-factor of this secondary assay was determined to be 0.58, suggesting it is an excellent assay for screening. Etodolac, nepafenac, aloperine, protionamide, and olmesartan showed significant neuroprotection and was also validated by blinded manual DA neuronal counting. To determine whether these compounds are broadly relevant for neuroprotection, we tested them on a conduritol-b-epoxide (CBE)-induced Gaucher disease (GD) model, in which the activity of glucocerebrosidase (GBA), a commonly known genetic risk factor for PD, was inhibited. Aloperine, olmesartan, and nepafenac showed significant protection of DA neurons in this assay. Together, this work, which combines high content whole organism in vivo imaging-based screen and bioinformatic pathway analysis of the screening dataset, delineates a previously uncharted approach for identifying hit-to-lead candidates and for implicating previously unknown pathways and targets involved in DA neuron protection.

Phytochemicals of Avocado Residues as Potential Acetylcholinesterase Inhibitors, Antioxidants, and Neuroprotective Agents.

Avocado (Persea americana) is a widely consumed fruit and a rich source of nutrients and phytochemicals. Its industrial processing generates peels and seeds which represent 30% of the fruit. Environmental issues related to these wastes are rapidly increasing and likely to double, according to expected avocado production. Therefore, this work aimed to evaluate the potential of hexane and ethanolic peel (PEL-H, PEL-ET) and seed (SED-H, SED-ET) extracts from avocado as sources of neuroprotective compounds. Minerals, total phenol (TPC), total flavonoid (TF), and lipid contents were determined by absorption spectroscopy and gas chromatography. In addition, phytochemicals were putatively identified by paper spray mass spectrometry (PSMS). The extracts were good sources of Ca, Mg, Fe, Zn, ω-6 linoleic acid, and flavonoids. Moreover, fifty-five metabolites were detected in the extracts, consisting mainly of phenolic acids, flavonoids, and alkaloids. The in vitro antioxidant capacity (FRAP and DPPH), acetylcholinesterase inhibition, and in vivo neuroprotective capacity were evaluated. PEL-ET was the best acetylcholinesterase inhibitor, with no significant difference (p > 0.05) compared to the control eserine, and it showed neither preventive nor regenerative effect in the neuroprotection assay. SED-ET demonstrated a significant protective effect compared to the control, suggesting neuroprotection against rotenone-induced neurological damage.

Small molecule C381 targets the lysosome to reduce inflammation and ameliorate disease in models of neurodegeneration

SignificanceNeurodegenerative diseases are poorly understood and difficult to treat. One common hallmark is lysosomal dysfunction leading to the accumulation of aggregates and other undegradable materials, which cause damage to brain resident cells. Lysosomes are acidic organelles responsible for breaking down biomolecules and recycling their constitutive parts. In this work, we find that the antiinflammatory and neuroprotective compound, discovered via a phenotypic screen, imparts its beneficial effects by targeting the lysosome and restoring its function. This is established using a genome-wide CRISPRi target identification screen and then confirmed using a variety of lysosome-targeted studies. The resulting small molecule from this study represents a potential treatment for neurodegenerative diseases as well as a research tool for the study of lysosomes in disease.

Evaluation of the Biological Potential of Himanthalia elongata (L.) S.F.Gray and Eisenia bicyclis (Kjellman) Setchell Subcritical Water Extracts.

Neuroprotection is a need that remains unmet in treating chronic neurodegenerative disorders, despite decades of extensive research. To find new neuroprotective compounds, extracts of Himanthalia elongata (L.) S.F.Gray and of Eisenia bicyclis (Kjellman) Setchell were obtained through subcritical water extraction applying a four-step temperature gradient. The fractions obtained were screened against brain enzymes involved in neurodegenerative etiology, namely in Alzheimer’s and Parkinson’s diseases, and against reactive oxygen and nitrogen species, all contributing factors to the progression of neurodegeneration. Results showed no significant enzyme inhibition but strong radical scavenging activities, particularly in the fourth fraction, extracted at the highest temperature (250 °C), highlighting their ability to retard oxidative and nitrosative stresses. At higher temperatures, fractions were composed of phenolic compounds and Maillard reaction products, a combination that contributed to their antioxidant activity and, consequently, their neuroprotective properties. All fractions were evaluated for the presence of iodine, 14 organochlorine and 7 organophosphorus pesticides, and pharmaceuticals used in Alzheimer’s and Parkinson’s diseases (14), psychiatric drugs (8), and metabolites (8). The fractions studied did not present any of the screened contaminants, and only fraction 1 of E. bicyclis should be used with caution due to iodine content.

Zebrafish drug screening identifies candidate therapies for neuroprotection after spontaneous intracerebral haemorrhage.

ABSTRACTDespite the global health burden, treatment of spontaneous intracerebral haemorrhage (ICH) is largely supportive, and translation of specific medical therapies has not been successful. Zebrafish larvae offer a unique platform for drug screening to rapidly identify neuroprotective compounds following ICH. We applied the Spectrum Collection library compounds to zebrafish larvae acutely after ICH to screen for decreased brain cell death and identified 150 successful drugs. Candidates were then evaluated for possible indications with other cardiovascular diseases. Six compounds were identified, including two angiotensin-converting enzyme inhibitors (ACE-Is). Ramipril and quinapril were further assessed to confirm a significant 55% reduction in brain cell death. Proteomic analysis revealed potential mechanisms of neuroprotection. Using the INTERACT2 clinical trial dataset, we demonstrated a significant reduction in the adjusted odds of an unfavourable shift in the modified Rankin scale at 90 days for patients receiving an ACE-I after ICH (versus no ACE-I; odds ratio, 0.80; 95% confidence interval, 0.68-0.95; P=0.009). The zebrafish larval model of spontaneous ICH can be used as a reliable drug screening platform and has identified therapeutics that may offer neuroprotection. This article has an associated First Person interview with the first author of the paper.

Various facets of excitotoxicity

Aim: Excitotoxicity results from unusually increased activation of excitatory amino acid receptors leading to neuronal death. Since glutamate is the main excitatory neurotransmitter in the central nervous system, it is also the most common excitotoxicity trigger. This uncontrolled neuronal response participates in various neurodegenerative diseases, such as ischemia, hypoglycemia, Huntington’s, Parkinson’s and Alzheimer’s disease. Thus, the investigation in the field expanded a lot in the past decade, leading to in vitro modelling adaptations. However, much performed work on glutamate-induced excitotoxicity is methodologically inconsistent in the literature. The field lacks reproducibility, which is one of the main fundaments of empirical science. In this regard, the literature was summarized and the main methodological features were critically evaluated, aiming to guide the researchers that are starting in the field. Methods: Published data since 1985 from PUBMED were collected and analyzed to observe which in vitro experimental conditions of excitotoxicity were reproducible. The suggested methods were based on the characteristics of excitotoxicity, such as abnormal intracellular calcium mediated signaling, mitochondria impairment, reactive oxygen species accumulation and cell death. Various conditions and comparative controls were used to design the standard investigation of excitotoxicity, such as culture medium content (presence of glutamate and aspartate), time interval of induction and the concentration of the inductor, based on the most reproducible published ones. Results: Our results and critical analysis point to some experimental conditions to consider, such as primary cultured neurons are more sensitive to glutamate and the response obtained is more robust than in other models; excitotoxicity mediated effects are better observed one hour following the stimulus; the culture medium should contain low levels of glutamate or aspartate or glycine. Online available phosphoproteomic data on excitotoxicity using the primary cortical neurons in vitro model supported the same conditions proposed by us. Conclusions: This manuscript will facilitate the design of any research for excitotoxic or neuroprotective compounds in physiological and pathophysiological conditions by standardizing and improving experimental conditions.

Piperlongumine as a Neuro-Protectant in Chemotherapy Induced Cognitive Impairment.

Advances in the early diagnosis and treatment have led to increases in breast cancer survivorship. Survivors report cognitive impairment symptoms such as loss of concentration and learning and memory deficits which significantly reduce the patient’s quality of life. Additional therapies are needed to prevent these side effects and, the precise mechanisms of action responsible are not fully elucidated. However, increasing evidence points toward the use of neuroprotective compounds with antioxidants and anti-inflammatory properties as tools for conserving learning and memory. Here, we examine the ability of piperlongumine (PL), an alkaloid known to have anti-inflammatory and antioxidant effects, to play a neuroprotective role in 16-week-old female C57BL/6J mice treated with a common breast cancer regimen of doxorubicin, cyclophosphamide, and docetaxel (TAC). During social memory testing, TAC-treated mice exhibited impairment, while TAC/PL co-treated mice did not exhibit measurable social memory deficits. Proteomics analysis showed ERK1/2 signaling is involved in TAC and TAC/PL co-treatment. Reduced Nrf2 mRNA expression was also observed. mRNA levels of Gria2 were increased in TAC treated mice and reduced in TAC/PL co-treated mice. In this study, PL protects against social memory impairment when co-administered with TAC via multifactorial mechanisms involving oxidative stress and synaptic plasticity.

2021 Workshop: Neurodegenerative Diseases in the Gut-Brain Axis—Parkinson's Disease

2021 Workshop: Neurodegenerative Diseases in the Gut-Brain Axis—Parkinson's Disease

The effect of ACTH4-10Pro8-Gly9-Pro10 on neurotrophin-3 expression in Sprague Dawley rat on acute spinal cord injury

Background: Neurotrophic factors such as NT-3 play an important role in spinal cord regeneration, contributing to spinal cord regeneration assisting functional improvement in SCI. ACTH4-10Pro8-Gly9-Pro10, an analog of the N-terminal fragment (4-10) adrenocorticotropic hormone, is one of the neuroprotective compounds that can increase NT-3 levels in brain ischemia. Therefore, we conducted a study with experimental animals to determine the effect of NT-3 expression on ACTH4-10Pro8-Gly9-Pro10 administration in acute compression SCI.Method: We used Sprague Dawley rats with acute compression SCI model using 20 gr and 35 gr aneurysm clips. ACTH4-10Pro8-Gly9-Pro10 was administered intranasally to the treatment group, and 0.9% NaCl was administered intranasally to the positive control group. Both of the groups then terminated at 3 and 6 hours.Results: In rats with mild SCI that were given ACTH4-10Pro8-Gly9-Pro10, the NT -3 expression after 3 hours and 6 hours was 14 (12-17) and 10 (7-13). In rats with severe SCI given ACTH4-10Pro8-Gly9-Pro10, the NT-3 expression after 3 hours and 6 hours was 9 (6-11) and 8 (7-10). Intranasal administration of ACTH4-10Pro8-Gly9-Pro10 showed higher NT-3 expression than the group with 0.9% NaCl in mild and severe SCI.Conclusion: Intranasal administration of ACTH4-10Pro8-Gly9-Pro10 can increase NT-3 expression in mild and severe acute SCI at 3 and 6 hours. Expression of NT-3 in the group with ACTH4-10Pro8-Gly9-Pro10 mild acute SCI was higher than in the group with severe acute SCI. Further research needs to be done to determine the neuroregeneration effect of ACTH4-10Pro8-Gly9-Pro10 on SCI.

Cholinesterase inhibitory activities of neuroprotective fraction derived from red alga Gracilaria manilaensis

Anti-cholinesterase (ChE)s are commonly prescribed as the symptomatic treatment of Alzheimer’s disease. They are applied to prevent the breakdown of neurotransmitter acetylcholine (ACh) that bind to muscarinic and nicotinic receptors in the synaptic cleft. Seaweeds are one of the richest sources of bioactive compounds for both nutraceuticals and pharmacognosy applications. This study aimed to determine the anti-ChEs activity of Gracilaria manilaensis, one of the red seaweeds notables for its economic importance as food and raw materials for agar production. Methanol extracts (GMM) of G. manilaensis were prepared through maceration, and further purified with column chromatography into a semi-pure fraction. Ellman assay was carried out to determine the anti-acetylcholinesterase (AChE) and anti-butyrylcholinesterase (BuChE) activities of extracts and fractions. Lineweaver-Burk plot analysis was carried out to determine the inhibition kinetic of potent extract and fraction. Major compound(s) from the most potent fraction was determined by liquid chromatography-mass spectrometry (LCMS). GMM and fraction G (GMMG) showed significant inhibitory activity AChE with EC50 of 2.6 mg/mL and 2.3 mg/mL respectively. GMM and GMMG exhibit mixed-inhibition and uncompetitive inhibition respectively against AChE. GMMG possesses neuroprotective compounds such as cynerine A, graveolinine, militarinone A, eplerenone and curumenol. These findings showed a promising insight of G. manilaensis to be served as a nutraceutical for neuronal health care in the future.